Re: Read from directory list...

Use globbing to obtain a subset of the directory, then collect the content in a list.

#!/usr/bin/perl -w
my @files = <*.pl>;  # get list of .pl files in this dir
my @content;
foreach my $file (@files) {
    if (-f $file && open(FH,"<","$file")) {
        @content= (@content, <FH>);  # add filecontent
        close(FH);
    }
}
# optionally: chomp @content

print "$_" foreach @content;
[download]

Comment on Re: Read from directory list... Download Code

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Re^2: Read from directory list... by johngg (Canon) on Feb 06, 2007 at 23:31 UTC
When you add each file's lines to `@content` you are copying the entire array every time around the loop. This could quickly get expensive. It would probably be better to `push` onto the array, so instead of `@content= (@content, <FH>);` [download] you could do `push @content, <FH>;` [download] I ran a benchmark of these two methods on a sample of 65 scripts totalling 2082 lines, "Copy" being your original and "Push" my suggested alternative. Here's the benchmark code Read more... (1041 Bytes) and here's the result `Rate Copy Push Copy 2.32/s -- -94% Push 41.9/s 1710% --` [download] As you can see, copying the array each time takes a lot of resources. Cheers, JohnGG	[reply] [d/l] [select]

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Re^2: Read from directory list...
by johngg (Canon) on Feb 06, 2007 at 23:31 UTC

@content

push

@content= (@content, <FH>);
[download]

you could do

push @content, <FH>;
[download]

I ran a benchmark of these two methods on a sample of 65 scripts totalling 2082 lines, "Copy" being your original and "Push" my suggested alternative. Here's the benchmark code

Read more... (1041 Bytes)

and here's the result

       Rate  Copy  Push
Copy 2.32/s    --  -94%
Push 41.9/s 1710%    --
[download]

As you can see, copying the array each time takes a lot of resources.

Cheers,

JohnGG

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